FP-TB-10 Operating Instructions
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Some dual-channel modules, such as the thermocouple and
four-wire RTD modules, provide other means of making
field-wiring connections.
Update Rates
The FP-TB-10 continuously scans through its six dual-channel
modules, updating outputs and reading inputs. The scan rate varies
depending on the modules in the FP-TB-10. Empty slots and
digital modules add 0.2 ms each to the scan time, and analog
modules add 1.5 ms each. The sum of these six times is the total
scan time. For example, an FP-TB-10 with two FP-AI-C020
modules, one FP-DI-DC, and three empty slots has a total scan
time of 3.8 ms (4 × 0.2 ms + 2 × 1.5 ms).
Each I/O module makes data available to or reads data from the
network module once per scan time. However, the network module
makes data available to and receives data from the network at rates
that are independent of the operation of the FP-TB-10 and the
dual-channel modules. Refer to the network module user manual
for more details on the operation and throughput of your particular
network.
Power Requirement (P+)
The FP-TB-10 and the dual-channel modules are powered through
the local backplane bus from the FieldPoint network module. An
FP-TB-10 with I/O modules may require more than the nominal
power allocated to an I/O module from the network module. In
some applications, this power requirement could limit the number
of I/O modules that you can connect to a single network module.
When defining a FieldPoint system that uses an FP-TB-10,
calculate the total power consumption of the FP-TB-10 with its
dual-channel modules, as well as the power consumption of the
other I/O modules in the system. The total power consumption
of all these modules must be less than 9 W. The FP-TB-10 alone
requires 0.20 W of power; add to this the individual power
requirements of the dual-channel modules given in the
section.
For example, an FP-TB-10 with three FP-AO-C020 dual-channel
modules and two FP-AI-C020 dual-channel modules requires
4.25 W of power (0.20 W + 3 × 1.1 W + 2 × 0.375 W). A bank
of FieldPoint modules including two such FP-TB-10 bases uses
8.5 W of power—nearly the entire 9 W limit.
